1. Field of the Invention
The present invention relates to a heat dissipation apparatus for a notebook computer and, more particularly, to a heat dissipation apparatus for a notebook computer with a low flow resistance design.
2. Description of the Related Arts
It is well known that computers and other electronic devices commonly include components that produce heat while operating. There is no doubt that heat dissipation has been one of the biggest problems in computer design. To maintain computers or electronic devices within operating temperature limits, various types of heat dissipation system have been proposed for removing heat from the heat-producing components. In earlier years, the passive cooling method is proposed to solve the heat dissipation issue. However, during the past few years, the heat generated by the CPU of computer has substantially increased from 7W, 8W, 12W, 17W, . . . , up to 60W. It is almost ten times more than the heat generated by CPU before. Not comparably, materials of good heat dissipation property are developed slowly. For example, the thermal conductivity coefficient of aluminum used in early days was about 200 w/m xc2x0 C., and the thermal conductivity coefficient of copper used nowadays is about 400 w/mxc2x0 C. Therefore, the heat dissipation problems of computer become much more difficult than ever.
Fortunately, the introduction of heat pipe solves the heat dissipation problem. Material of the heat pipe is just a combination of copper and fluid. But, the thermal conductivity coefficient of the heat pipe is increased to about 10000 w/mxc2x0 C. which is fifty times more than that of aluminum. That is, the heat pipe has the potential of rapidly transferring heat away from a microprocessor chip or other heat-generating components. The application of heat pipe to the notebook computer not only solves the heat dissipation problem, but also has the benefit of being easily manufactured. Gradually, the heat pipe is normally implemented in notebook computers to take heat away.
However, heat dissipation simply based on conduction mechanism does not satisfy today""s need. How to incorporate heat-exchange behavior transferring heat to the atmosphere is another key aspect for heat dissipation of notebook computers. The heat-exchange occurs between cool air and the heat dissipation apparatus. Forcing the heat-exchange to be accomplished by fan is one of most effective ways to transfer heat to the atmosphere.
FIG. 1 shows a notebook computer of a conventional heat dissipation apparatus. The notebook computer includes a CPU, an air inlet, and an air outlet. The conventional heat dissipation apparatus includes a fan, a heat sink, a conduction block, and a heat pipe. The heat generated by the CPU is absorbed in the conduction block. The heat pipe is connected to the conduction block and the heat sink. The heat pipe is configured for transmitting heat in the conduction block to the heat sink. Then, the heat transferred to the heat sink is carried away by air flow generated by the fan. However, the fan mentioned above is often vertically set up in a notebook computer casing. When the notebook computer size is destined to shrink, the heat dissipation apparatus is restricted to a limited space. Due to the thickness of the limited space of the notebook computer, it is not feasible to increase the fan in number and size. Moreover, the air flow direction passing through the air inlet and the air outlet are nonparallel to each other. Consequently, the heat dissipation apparatus results in large air flow resistance and inefficient heat dissipation.
FIG. 2 shows another notebook computer of a conventional heat dissipation apparatus. The notebook computer includes a CPU, an air inlet, and an air outlet. The conventional heat dissipation apparatus includes a flat cartridge with a fan positioned thereon, an air passage, a heat sink adjacent to a sidewall of the flat cartridge, a conduction block, and a heat pipe. The heat generated by the CPU is absorbed in the conduction block. The heat pipe is connected to the conduction block and the heat sink. The heat pipe is configured for transmitting heat in the conduction block to the heat sink. Then, the heat transferred to the heat sink is carried away by air flow generated by the fan. The fan mentioned above is horizontally positioned on the flat cartridge in a notebook computer casing. Due to the fan is horizontally positioned, it is possible to improve the capability of heat dissipation by using a larger fan. However, the air directions passing through the air inlet and the air outlet are still nonparallel to each other. Accordingly, the heat dissipation apparatus mentioned above also results in large air flow resistance and disappointing heat dissipation efficiency.
The present invention provides a heat dissipation apparatus to promote the heat dissipation efficiency for a notebook computer and, more particularly, for a notebook computer with high flow rate and high input power.
The present invention adopts heat pipe to carry heat aside from the CPU. Afterwards, the heat is carried away by fans. Furthermore, the present invention places emphasis on air flow direction. The air flow directions passing through the air inlet and the air outlet are parallel to each other. Drawbacks in prior arts are eliminated to improve heat dissipation more effectively under the limitation of restricted space.
The present invention provides a heat dissipation apparatus including a heat sink, at least one fan, a conduction block, and a heat pipe. The heat sink is used for transmitting heat. The conduction block is closely contacted to an upper surface of a CPU in a notebook computer for absorbing heat from the CPU. The heat pipe is connected to the conduction block and the heat sink. The heat pipe is configured for transmitting heat in the conduction block to the heat sink. Then, the heat transferred to the heat sink is carried away by air flow generated by the fan. In the present invention, the air flow directions passing through an air inlet and an air outlet are parallel to each other. Therefore, the air flow resistance is reduced to accelerate the heat dissipation.
Notebook computer, in accordance with the present invention, in one embodiment, includes a CPU, an air inlet, an air outlet, and a heat dissipation apparatus. The heat dissipation apparatus includes a heat sink, at least one fan, a conduction block, and a heat pipe. The air inlet is used to inhale air, and the air outlet is used to exhaust air. The heat sink is used to transmit heat. The conduction block is closely contacted to an upper surface of the CPU in the notebook computer for absorbing the heat from CPU. The heat pipe is connected to the conduction block and the heat sink. The heat pipe is configured for transmitting heat in the conduction block to the heat sink. Then, the heat transferred to the heat sink is carried away by air flow generated by the fan. In the present invention, the air flow directions passing through the air inlet and the air outlet are parallel to each other. Therefore, the air flow resistance is reduced to accelerate the heat dissipation.